Coating glass fabric



Patented Sept. 17, 1940 UNITED STATES COATING GLASS FABRIC Cornelius Anthony Alt, Newburgh, N. Y., assignor to E. I. du Pont de Nemours 82 Company, Wilmington, DeL, a corporation of Delaware No Drawing. Application February 25,1937,

. I Serial No. 127.192

1 claim. (Cl. iii-cs) This invention relates to coated fabrics and methods of producing the same. It especially relates to the coating of woven glass fabrics.

It is well known that coated fabrics in which 5 W001, cotton and the like constitute the base material are inflammable, and much time and money has been spent in an effort to secure a satisfactory method of fireproofing the same. It is also known that such coated fabrics are frequently attacked 0 by fungi and are often deleteriously affected by actinic rays. The tendencyof coated cotton fabrics to shrink has been a source of inconvenience and expense for many years. In work directed to overcoming the aforementioned difficulties, it

'15 has been found that a satisfactory product may be obtained by coating woven glass fabrics with suitable coating compositions.

The absence of a nap on glass fabrics similar to that encountered in the case of cotton fabrics, and the flaking off of fine particles of glass from the fiber surface, whereby adhering matter is loosened, has complicated the problem and retarded the development of a coated glass fabric having desirable characteristics.

25 This invention had for an object the production of a coated fabric which was not inflammable. which was not attacked by fungi, which was not deteriorated upon exposure to actinic rays, and which did not shrink in the manner 30' common to cotton textiles. Another object-was the preparation of a coated woven glass fabric, the coating of which was not loosened and otherwise detrimentally affected by chemical and physical changes taking place in the glass of the fabric 35 is it aged. A still further object was the preparation of a superior type of coated woven glass fabric. A general advance in the art and other objects which will appear hereinafter are also contemplated.

40 It has now been found that a fabric having the aforementioned desirable properties, and accom-' plishing the aforementioned objects, may be prepared by coating a woven glass fabric with a coating composition selected from the group consist- 45 ing of cellulose derivative coating compositions, synthetic resin coating compositions, natural resin coating compositions and protein type coating compositions.

Theaforegoing objects andrelated ends are ac 50 complished in the manner set out in the following description, in which are disclosed details of what is believed to be the best mode for carrying out the invention. Quantities aregiven in 'parts by weight throughout the application unless 55 otherwise indicated.

Woven glass yarn is prepared by making glass strands having a diameter on the order of th of an inch, twisting these strands into a yarn and weaving the same. The twisting and weaving are :0 carried out in the manner usually employed with cotton fibers. About 100 strands are necessary to produce a thread the size of the familiar No. 50

cotton thread. The production of the glass fibers Illustrative specific coating compositions for this purpose follow.

Example I Per cent by weight Cellulose nitrate 14.0 Castor oil 18.6 Pigment 23.4 Ethyl acetate 4 17.6 Ethyl alcnhnl 26.4

Example II Cellulose nitrate 13.7 Dibutyl phthalate 11.4 Pigment 22.8 Ethyl acetate 20.8 Ethyl alcohol 31.3

Example 1!! Cellulose nitrate 18.7 Copolymer of vinyl acetate and vinyl chloride 80-20 15.3 Tricresyl phosphate 16.3 Methyl ethyl ketone 28.5 Ethyl acetat 10.8 Ethyl alcohol 104 Example IV Cellulose acetate 8.65 Cellulose nitrate 5.77 Castor oil 5.90 Actnnp 12.48 Ethyl acetat 36.34 Denatured alcohol (23) 22.16 Dibutyl tartrate 8.70

The denatured alcohol used in the above formulation is that corresponding to Internal Revenue Bureau formula 2-B. It is an alcohol denatured with benzene by mixing the two in the ratio of 100 gallons of 95% by volume of ethyl alcohol to one-half gallon of benzene.

' Example V Percent by weight Cellulose ace 5.76 Cellulose nitrate 8.64 Castor oil 4.80 Dibutyl tartrate 1.92 Acto 9.21 Ethyl acetat 31.79 Denatured alcohol (213) 37.88

Example VI Cellulose acetate 4.62 Cellulose nitr 6.93 Castor oil 21.45 Aceto 8.25 Ethyl ace 23.76 Denatured alcohol (2B) 34.99 Example VII Cellulose acetate 14.0 Dibutyl tartrate 14.0 Pigment 23.4 Acetone 20.0 Ethyl alcohol 28.6

Example VIII Methyl methacrylate 21.0 Diethyl phthalate; 18.9 Toluene 50.1 Ethyl alcohol 10.0 Example IX Vinylite 80" 35.2 Methyl ethyl ketone 47.1 I Pigment 5.9 Tricresyl phosphate 11.8

The Vinylite 80 is a copolymer of vinyl acetate and vinyl chloride, in which the acetate constitutes 80% of the mixture.

Dye solution The dye solution in the above formulation consists of the following:

Per cent by weight Luxol dy 33.33 Monoethyl ether of ethylene glycol 66.67

"Luxol is a trade name for spirit soluble dyes.

These products are' covered by U. S. Patent 1,674,128 issued on June 19, 1928.

The following represents a partial list of such dyes which may be used singly or in combination:

Luxol Fast Orange E Luxol Fast Scarlet'C Luxol Fast Red D Luxol Fast Black L Luxol Fast Yellow T and VI are especially suitable. for application over In the above examples calling for pigment, the following represents a partial list which may be used singly or in combination:

Bone black.

In addition to the above, lakes may also be usedto advantage. Metallic flakes such as aluminum or aluminum bronze may be used to produce metallic effects. Pigments or dyes may when desired be incorporated in the above examples which do not recite pigment in the formula.

The coating compositions of Examples IV, V

the various cellulose derivative type coating compositions recited in other examples to produce special surface effects.

Variations in translucency and transparency may be obtained by suitably regulating the index at of refraction of the coating composition applied to the woven glass fabric. Films of coating composition having an index of refraction equal to or closely approaching that of the woven glass base fabric may be used advantageously when a 8! coated product having a smooth surface and a suitable approach to transparency is desired. Coating compositions producing such films include suitably softened and/or plasticized cellulose derivative compositions, for example, cellulose nitrate and cellulose acetate containing compositions and alkyl or aryl esters of methacrylic acid. Other coating compositions which meet these requirements may also be used.

The character of the adherence of the cellu- I lose derivative coating compositions, particularly in the case of cellulose nitrate compositions, to the base fabric is improved by preliminarily coating the base material with a thin continuous coat of a natural resin or a synthetic resin. The con- 5 tinuous film of natural or synthetic resin acts as a barrier to the alkali present in the glass fibers or on their surface, and prevents the alkali from contacting the cellulose nitrate. Such specific resins and like bodies as shellac, copal, sandarac, 5

kauri, phenol formaldehyde condensates, urea formaldehyde condensates, polyhydric alcoholpolybasic acid (alkyd) resins, esters of acrylic acid, and methyl or higher esters of methacrylic acid, warrant special mention. These intermea diate coatings may be applied by spreading the particular resin carried in a suitable solvent or suspension medium on the fabric. and thereafter removing the solvent.

While cellulose nitrate and cellulose acetate 6 have been disclosed in the specific examples, it will be understood that these are replaceable by other cellulose esters, for example, cellulose propionate and cellulose but'yrate, and by cellulose others such as methyl cellulose, ethyl cellulose, 7 and benzyl cellulose. I

The softener for-the cellulose derivative and the cellulose derivative coating composition may be of any suitable type, a. great variety of which are known to those skilled in the art. Such spe- 7 ciflc types as treated or untreated vegetable and animal oils and .synthetic resins merit special mention..-

The compositions may be applied to the glass fabric by methods well known in the art of coating fabrics, such as by doctor knife, spray coating, roller coating, etc. In accordance with conventional coating practice, each coat may be suitably dried by passing through a heated chamber, or otherwise, before a subsequent coat is applied, in those cases where it is desired to have. a film composed of a plurality of coatings.

The amount of coating applied may vary over a wide range, and will be governed largely by the weight of the glass fabric to which the coating is applied, and by the intended use of the finished product.

Woven glass fabrics are obtainable in a variety of weaves and weights. Among the types which have been found especially'suitable for use in this invention are 2.10-30"-3/1 twill weave fabric (thickness .015%), and a 1.60-40" broken twill weave fabric (thickness .015%). This twill weighs 9,.12 ounces per square yard and the broken twill weighs 9.0 ounces per square yard.

The preferred form of the invention utilizes a woven glass yarn base. Felted glass yarns, i. e.,- non-woven yarns, are contemplated by the invention.

The coated woven glass fabrics may be embossed by methods fabrics.

applicable to coated cotton The products of thisdnvention are suitable for. such specific uses as motion picture screens. 'window shades, book covering material, weatherresisting tarpaulin, airplane coverings, wall coverings, window drapes, wearing apparel, outdoor upholstery material, fire-resistant 'sheet material, and the like. Such products have'the advantages that they have high tensile strength, that they are chemically inert, that they are not weakened by actinic rays, that they are not attacked by fungi, that they do not shrink like coated cotton materials, and that they are fireresistant.

As many apparently widely different embodiments of this invention may be made without departing from the spirit and scope thereof, it

Per cent by weight. Cellulose nitrate 14.0 Castor oil--- 18.6 Pigment... 23.4 Ethyl acetate 17.6 Ethyl alcohol 26.4

and thereafter drying. v

I CORNELIUS ANTHONY ALT. 

